The Black Guard Swordsmith is a level 62 elite armored skeleton in the "Scourge" side of Stratholme. He does not appear normally in the instance but will appear when a player tries to pick up a parchment called Blacksmithing Plans. The Swordsmith will appear and will try to kill the players.

The Blacksmithing Plans appear to the right of the stairs of the first ziggurat. Baroness Anastari appears at the top of that ziggurat. It's best to clear out any enemies in the area before trying to trigger the Swordsmith.